Refrigerating apparatus



March 24, 1931.

s. E. WEISSENBURGEIR ET AL REFRIGERATING APPARATUS CONDENSER COILEXPANSION COIL EXPANSION VALVE C OMPRESSOR Inventors G. E. WeissenburgerG. L. Weissenbu rger Att'y. l

Patented Mar. 24, 193 1 GEORGE E. WEISSENIBURGER AND'GEORGE I.WEISSENBUBGER, OF KEOKUK, IOWA REFRIGERATING APPARATUS Application-fl1ed December 80, 1829. Serial No. 417,834.

Our in. ention relates to a ,refrigerating system and is particularlydirected to providing means for preventing the trapping of lubricant inthe refrigerant receiver. 7

In a refrigerating system a portion of the oil placed in the crank caseof the compressor for lubricating its moving parts will work past thepiston and be carried over into the system together with the compressedrefrig- 10 erant. such oil should be returned to the compressor tomaintain proper working conditions in the system. If, however, the oilis of less specific gravity than the liquefied refrigerant and is notwholly soluble therein, it will float on the surface of the refrigerantand consequently willbe trapped in the refrigerant receiver or, in caseno receiver is used, in some other part of the system, such as thecondenser. This tra ping of oil not only reduces the capacity of thesystem for containing refrigerant but also interferes with the properlubrication of the compressor with resultant liability of injury to itsmoving parts.

The object of our invention is to provide float controlled means forvarying the height of the point of discharge from the receiver, thusmaintaining a uniform amount of lubricant in the receiver irrespectiveof the amount 7 30 of refrigerant therein. In this manner we.

prevent the trapping of additional lubricant with its resultantobjectionable features.

In the accompanying drawings, which illustrate a refrigerating system ofthe compressor-condenser-expander type having our invention embodiedtherein, Figure l is a vertical section through the receiver, the otherparts of the system being shown diagrammatically, and Figure 2 is asectional view of a modified form of receiver.

Our system comprises a compressor 1, a condenser coil 2, a receiver 3,.an expansion valve 4, and an expansion coil 5. Any suitable liquefiablegas, such as sulphur dioxide S0 may be used for the refrigerant. fterbeing compressed in the compressor this refrigerant passesthrough a pipe6 to the condenser coil whereit is liquefied and discharged into thereceiver. The objectof this receiver is to hold a surplus supply of theliquefied refrigerant to compensate for variation in the operation ofthe system.

Liquefied refrigerant passes from the receiver through a pipe 7 to theexpansion valve and thence into the expansion coil from which it isreturned in gaseous form to the compressor through pipe 8.

Liquefied refrigerant 9 enters the receiver 3 (Figure 1) from thecondenser coil 2 and, owing to its greater density, lies on the bottomof the receiver, being covered by a body of oil 10 which has beencarried over from the compressor with it. In the form of Figure 1 thepipe-7 projects vertically into the receiver and is open at its upperend. This upper end is surrounded by. a movable tube 11 controlled by afloat 12. The float is preferably spherical in form and the tubepreferably passes centrally through and is rigidly secured to it. Thepipe forms a guide for the tube in its vertical movement responsive tothe buoyance of the float and the tube is somewhat larger in diameterthan the pipe so as to provide an annular space 13 between the two partsfor the passage of liquid from the receiver to the open upper end of thepipe. lube 11 has its upper end closed but is 'open at its lower end toprovide a downwardly openlng outlet 14 which rises and falls with thefloat, thus determining the level at which the liquid is discharged fromthe receiver to the expansion valve. Float 12 is so proportioned as tosize and weight that it will only sink a predetermined distance in theoil 10; for example, about one-half its diameter, as shown in thedrawings. This will determine the depth'of the layer of oil as thedividing .line A between the oil and refrigerant will coincide with theposition of the outlet opening 14. The volume of'refrigerant in thereceiver may change, owing to variations in the operation of the system,the float and the .oil

rising and falling in response to such change, and only refrigerant willpass through the receiver aslong as the amount of oil therein remainsconstant. However, as soon as additional oil is carried over into thereceiver the outlet opening 14 will be raised suflicient- 1y to causeoil in like amount to be discharged.

2 w I V 1,797,385

Thus the trapping of more than the predetermined quantity of oil isprevented. .In Figure2 we have shown a modification in the constructionof theidischarge means. 5 In thisforin-a tube is connected by aliquid-tight pivotjoint 16 to the discharge pipe 7 Thistubepassesthroughthe float 12 and hasits open. outer end curved downwardly toprovide the outlet opening 14, which'rises and falls with the floa l IHaving fully described our invention, what we claim as new'and desire tosecure by Letters Patent of the United States is:

1. In a refrigerating system, the combina- V 15 tion with a compressorand an expansion device, of a liquid receiver interposed between saidcompressor and expansion device and containing a refrigerant and alubricant of lower specific-gravity than the refrigerant,

of float'controlled discharge means operable at varying. levels -forlimiting the depth of v the lubricant. y

2. In a refrigerating system, the combination with a compressor and anexpansion de-- vice,:of a, liquid receiver interposed between saidcompressor and expansion device and containing a refrigerant andalubricant of lower specific avity'than the refrigerant, of a floatmovabl e in the receiver, said float being provided with adischargeopening movable therewith and communicating with the expansion device.

3. In a refrigerating system, a liquid receiver, a discharge pipeprojecting u wardly in said receiver, a verticallvinova le tubesurrounding said pipe, said tube being closed at its upper end and openat its lower end and forming a discharge conduit communicating with thedischarge pipe, and a. float in the re ceivercontrolling-the movement ofsaid tube.

In testimony whereof, we hereunto ai'fix our signatures, this 26th dayof December,

